Sun, 27 May 2012 03:48:18 -0800WeeblyTue, 07 Jun 2011 19:39:06 -0800http://www.ladysilkworm.com/1/post/2011/06/diapause-vs-non-diapause-process.html.
If the P eggs hatched in spring, their F gen will hatch in 2 weeks.
If the P eggs are hatched in Summer/Fall, their eggs will go into diapause. Simple as that. These are what they call bivoltine.

But sometimes we don't get uniformity in diapause. I think it has to do with the hybridization of the silkworms of today. Most of the time, it is a bi and a single voltine cross breed. When you incubated the P eggs in fluctuating temperatures, the F egg neurosis sorta takes it on its own to determine whether it wants to hatch or hibernate. Some hibernate, and some don't, as we have seen often.  Personally I think they received mixed signals. Imagine if this happens in an egg factory.. but of course, it never will because they exercise precise temp and humidity control.

A skilled person can manipulate the P eggs by shortening/lengthening day hours vs night hours, and giving them specific temp to mimick the seasons.

However, this isn't true if you are working with chow, as the silkworms also take their queue from the nutritional values of the leaves.  I don't work with chow very much so I have not reached this part.


So, with the eggs that your moths laid, some will hatch and some will hibernate.

How do you tell them apart?

All eggs are laid creamy white (with slight diff amongst lines).. they will turn darker over days.  In general, if they remain same, they are not fertilized. But some times, (again, I think it is the hybridization) and I've seen this in my own rearings, some eggs develop head pigmentation= a small dot near the tip, but is still creamy.. and then it turns darker.. Those eggs are guaranteed hatch. Within the same group of eggs, some of them simply turn dark color without visible head pigmentation, but they end up hatching. Some will remain that dark brown or dark purple color and go into diapause.

What should you do then?

Like I said, in an egg factory, egg incubation is precisely controlled. For example, you can incubate bivoltine eggs at high temp in the spring, and they will lay hibernating eggs. Lab workers forcibly turned this strain to be single voltine because single voltine strains give out the best and highest yield in silk. But the bivoltine nature in them helps make them hardier.

Now, when your moths lay eggs, you technically should also give them temperature treatment but gradually lowering the temp day by day. But that is something we can't usually do in a regular household, unless it is fall season. But it is recommended (by experts and researchers) that you leave them out in room temp, for at least one month. Those that are meant to hatch will have hatched, those that are meant to go in diapause, will have done so completely, by reaching stage 18.. .. after  at least one month, you can then put the eggs in 40F fridge crisper in a ziploc and they will be good to catch after 2 months. The longer you leave them there, the lower the hatchability. You shouldn't store your eggs for more than 2 yrs as it weakens them .. 3rd 4th and  5 yrs get even more drastic, maybe as low as 10%.

If you have a lot of moths laying eggs, you'd be better off leaving all the eggs out for 1.5 to 2 months, let them all catch up to a certain stage in the embryonic development, giving the later eggs a chance to catch up.. then store away.  When you remove them from cold storage, you incubate them and black box them, they will hatch out pretty much at the same time.

There is a lot of advantage iin having them hatch at the same time. The laggards and late molters are very laborious to care for and are usually the first ones to go due to excessive pathogens as they have less resistance to germs and viruses than the larger ones, not counting the fact that they are easily bruised and crushed by layers of food.



]]>Sat, 14 May 2011 12:50:08 -0800http://www.ladysilkworm.com/1/post/2011/05/my-reply-to-charley.html(topicscharley@gmail.com)Sat, 14 May 2011 12:06:08

Thanks for posting this. I am interested in silkworm genetics, but don't know too much. I guess having hybrids would give you a variety of genes to pick out. I don't know about silkworms, but according to my father and some of my past experience, hybrid chickens are initially much larger and more productive because of something I believe is called hybrid vigor. However, after several generations of purposeful hybridizing and taking those hybrids and breeding them together, one gets chickens that are more and more like their tropical fowl ancestors. Are silkworms similar if you breed hybrids to each other over and over again?

****

Hi Charlie, Good question. I can tell this from what I have researched and from my own experience. I am sure Eika San can give you her professional and scientific opinion.
You are totally right about the hybrid vigor. In fact, everything we eat these days are pretty much genetically improved upon for a specific reason. Take tomatoes, for example, they are now better looking, longer shelf live, more uniform for better packaging, productivity/yield, flavor and color etc. Those big, funny looking tomatoes that we call heirlooms are no longer found commercially and they maintain the characteristics of their ancestors throughout.  Same in chickens. I own a few hybrid chickens as well. They are the eggs of free rangers. All mixed.  I have to say, they are for sure more "wilder" than your domestically bred ones.  In Chinese, we call it "tu ji". Their meat is probably tougher but more flavorful. Although only 2 months old chicks without a hen, they can fend off predators with their rambunctiousness, as opposed to my full grown, store bought silkie chickens which I've lost all to predators in the past month. Anyway, back to silkworms. Yes, hybrids are commercially bred for hardiness. What I have noticed though, from what I could remember, is that these hybrids (the zebras ones- can get really fat. Fattest I have seen.) They also tend to whip back more than the white ones I remember from my childhood. This is definitely an insect instinct.  If you have ever owned hornworms, hornworms tend to do this quite frequently. They whip back and can nip at you. (they are just caterpillars and I've bred some!).. in fact, the larger hornworms, when starved, can actually cannibalize the younger larva (I've read and heard from chameleon owners). Now, when you google on tiger silkworms, a lot of the chinese forums will mention that the tiger silkworms, when starve will eat the younger larva. I don't know if this is true or not, and don't intend on seeing this happen. For all I know, it could be just a myth or urban legends that chinese parents like to scare their kids with. But in thinking back about hornworm behavior, I can't come out and blatantly dispute that notion with the tiger silks.  With this brood of zebras that I am raising, I've noticed the whipping action more often. With my previous brood of silkworms, I noticed the moths tend to flutter quite a bit, and were escaping their rearing boxes. Remember Michelle, she said that she is keeping a line that she found to be 'flying' a bit.
Now, back to zebras and tigers, according to our friend, all colored lepidoptera are in general more hardy than the white ones, and by being hardy that usually means they are a multivoltine strain, coming from  warmer climates. Now, in linking back warmer climates with voltinity and hardiness, is it safe to say there is some reverence to hybridized silkworms displaying more of their innate insect characteristics?  It's all about selective breeding. All animals look for genetics outside of their community to bring in more genetic variety and vigor, for one purpose or another! And supposedly, if we eat more meat, we tend to grow more body/facial hair! LOL Am I making sense?

]]>Thu, 05 May 2011 09:19:57 -0800http://www.ladysilkworm.com/1/post/2011/05/if-i-were-to-buy-a-mulberry-tree-what-would-it-be.htmlTotally a weeping one. It gives easy access to picking, makes a great canopy and shade tree. If I had the room and can locate a weeping mulberry, I would be willing to pay $125-150 for a nice one.  It is easy to trim and makes a nice landscape. Just check out some of the images!
]]>Thu, 05 May 2011 06:05:37 -0800http://www.ladysilkworm.com/1/post/2011/05/silkworm-voltinity-to-come-later.htmlThis is your new blog post. Click here and start typing, or drag in elements from the top bar. ]]>Thu, 05 May 2011 06:04:01 -0800http://www.ladysilkworm.com/1/post/2011/05/how-come-not-all-the-silkworms-in-the-same-brood-look-the-same.htmlA customer brought to my attention that some of her silkworms have markings while others are completely white, and some have slight banding. I've answered variations of the same questions individually by email but thought this is a good time to blog about it.

Basically, all of the first hand silkworms available here are  in general 4 way hybrids. (sometimes 2 or 3 , but mostly 4). They are bred for commercial purposes, for recreational and for hardiness.  Most of the ones here are mixed in with a multivoltine line from a warmer climate area. We all know silkworms originated in Asia, but now we have European lines. I don't know how they go about claiming a line is specifically European, but  I guess if a line remains phenotypically the same and produce predictable generations for many many years, it can be recognized as standard.

Back to the question, there are no pure lines available, except those that are safely guarded in research institutions. You can obtain pure lines only in writing, and through exchange programs. Or a student obtains eggs and smuggles them out :)

When I started working with the silkworms in this country. ( I am not a researcher, just an enthusiast) I thought I wanted to isolate some of these desired traits from these every day silkworms. Specifically I wanted to separate out the white seductress from the masked face for the reasons that white seductress made a better canvass for coloring. But as I bred down the lines, despite the appearance of the chosen breeders, I ended up back breeding them, splitting up to the lines of the top origination.  This is why you end up with a variety. You can back breed, but I read that it will take you about 30 generations to get some uniformity, but not consistency. In simple classification, P1 stands for first parent, and F1 are for first gen hybrids.

The best breed that I enjoy working with are definitely the tiger silks. ( I think I should really call them Tiger hybrids now). When you breed them,  you will notice they are not all consistently the same darkness.  But those are usually culled, or fed off, and you would use only the darkest ones as your breeders. Keep working down the line, or rather UP the line to get them to have that gorgeous velvety skin. They do spin gold silk, but are coarse and small cocooned. In general, color silkworms are hardier but smaller in size, reaching only 2 inches and lay smaller eggs.

There are cocoons that are peanut sized,  round, or oval. The largest I have seen is a man's large toe size ( those silks are meant for silk duvets- imagine that!) and the smallest I've seen is the size my pinkie.


There is a lot more in this area. But this will do for now.



]]>Mon, 02 May 2011 17:42:04 -0800http://www.ladysilkworm.com/1/post/2011/05/dont-you-hate-it-when-you-buy-something-online-and-you-have-to-register-with-them-virtually-signing-your-life-away-ok-not-that-drastic-but-sure-is-cumbersome.htmlI wanted to buy something from an online seller.  Wasn't anything of absolute necessity, but every time I see that I have to register an account with them, I get so turned off.  Shopping online suddenly became terribly inconvenient and repelling. With that said, I have to admit, I LOVE paypal and I love weebly. It enabled an IT dummy like me to actually fulfill a fantasy. With my online store you can purchase items in very few quick clicks. How convenient is that? Wasn't it just last it last month when a security breach occurred with Epsilon, an e-marking fulfillment house that involved many of our banking services? How trustworthy can you be with giving away credit card  info to a merchant that you cannot address by first name? In effort to simplify life, it seems as if we've made it ever more complicated.
]]>Sun, 01 May 2011 17:13:47 -0800http://www.ladysilkworm.com/1/post/2011/05/raising-silkworms-for-silk.htmlThe main theme of my mission is to provide feeders and to supply interesting exotic silkworms to educators. But if you are looking to have spinnable silk, it is advised that you use leaves instead of chow. Keep the silkworms at 78 degrees and have food at ALL TIMES. Anything less than that you would prolong the larval life. Typically, larval stage is only about 28-30 days depending on lines, but if you starve them, keep them cold, they will NOT have produce good silk quality for you. Typically, the silkworms available here are meant as feeders and are commercially developed as hybrids with lines of different voltinity, which often is a bivoltine strain meant for hardiness. In general, these silkworms produce coarse silk, sometimes too thick that the moth has a hard time emerging, which means you will have to cut it out, or that the silk is thin and the cocoon is very small...  As I blogged earlier, my father is in China and is helping to obtain some silk quality eggs from a well known sericulture institute. Hope it all works out with that.
]]>Sun, 01 May 2011 16:59:50 -0800http://www.ladysilkworm.com/1/post/2011/05/black-box-technique-how-to-have-your-silkworms-hatch-at-the-same-time-to-save-work.htmlMost silkworm sellers just tell you to hatch them at a certain temp, but sometimes the hatch can take several days, and they don't tell you there are techniques that you can use in hatching. There was a 5 day period where I got up 2 x at night brushing kegos and going out to the yard to fetch fresh leaflets.  But now I just use chow in the beginning to save work, as the newborns simply crawl onto the chow themselves. However, if you want to save the manual labor of tending to silkworms at various stages, try this technique:

Simply cover or put your eggs as soon as you see they have turned gray in completely darkness. Remove the cover in 2 days and expose to light (not directly of course) in the morning.. You will see hundreds hatch out before your eyes almost instantly. Allow two hours for the rest. If there are eggs that still have not hatched, repeat your technique and expose to light the following morning.  This ensures most of your silkworms develop at around the same age.
]]>Sun, 01 May 2011 10:01:30 -0800http://www.ladysilkworm.com/1/post/2011/05/why-i-do-what-i-do.htmlHeck I am so busy with two boys, but I find the more projects I take on the more I feel self fulfilled. Although at times very exhausting, but I LOVE WHAT I DO!

I live in the suburbs of NY. I have only a .18 acre property. But I raise free range chickens (hatched in my incubator) and they are running lose on the neighbors now :( I am a broker for silkie chickens and I grow veggies. I've also planted some asian pear trees and apples and cherries. They are prepped  to yield hundreds of tasty fruits this year if the squirrels don't to get them before I do.

I was also a sugar glider breeder and successful bred 7joeys in only 1.5 yr. I started that hobby when I found a sick flying squirrel one day. I also take injured animals and bring them to rehab centers. Occasionally I go to live kill markets and have rescued rabbits, chickens and ducks on death row, in addition to incubating fertilized eggs found in nature. My rescue rabbit free ranged in my house and liked to poop on my leather couch. My best crop is cantaloupes, probably big, sweet, juicy enough to be in the guiness book of records!  I was a cosmopolitan gal that worked in the city for many years.. and a opera soprano with several competition titles, plus I have an MBA. Then I got laid off and had kids... in this time of recession when you have kids and can't find a job, you turn to your hobbies for inspiration.
]]>Sun, 01 May 2011 09:48:19 -0800http://www.ladysilkworm.com/1/post/2011/05/trimming-your-mulberry-bush.htmlYou can cut down the branches as you go, as this forces new shoots from the base. It takes time, but they will develop shoots, much like a bamboo forest.  But if you shouldn't cut all the branches down until the end of the season if you want it to remain a bush. This forces the trunk to harden (you are artificially dwarfing it, like you do with a bonsai) and many new shoots will spring up next season. If you want it to be a tree, leave the central branch, and let it develop smaller branches off the knots.
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